A Fully Description of Android OS

1. A Seminar Presentation On
“ ANDROID OPERATING SYSTEMS ”
Presented By – MATE GANESH KARBHARI------------------
T.E. ( Information Technology )
ZCOER, Pune.
Guide:
Prof. --------Mr. Mahesh Giri.-------------
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2. Contents
 Abstract
 Keywords
 Introduction
 Android Architecture
 Version History
 SSL
 Android Security
 Service
 Features
 References
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3. Abstract:-
 The android operating system is basically an operating system for mobiles and is rapidly
gaining market share, with dozens of smart phones and tablets either released or set to be
released.
 It is mobile operating system that uses a modified version of the Linux kernel 2.6. Google
developed Android as part of the Open Handset Alliance, a group of more than 30 mobile
and technology companies working to open up the mobile handset environment.
 Android's development kit supports many of the standard packages used by Jetty, due to
that fact and Jetty's modularity and lightweight foot print, it was possible to port Jetty to it so
that it will be able to run on the Android platform.
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4. Keywords:-
 Android.
 version history.
 android security.
 service.

5. INTRODUCTION:-
 Android is a software platform and operating system for
mobile devices, based on the Linux kernel, and developed
by Google and later the Open Handset Alliance.
 It allows developers to write managed code in the Java
language, controlling the device via Google-developed Java
libraries.

6. INTRODUCTION Cont:-
 Android is a freely downloadable open source software stack for mobile devices that
includes an operating system, middleware and key applications based on Linux and
Java.
 Google purchased the developer of Android in 2005, and Android was unveiled in 2007.
 Android has numerous developers writing applications (apps) all over the world. First of
all the developers write their script in Java, and then download the apps from the third
party sites or online stores.
 In February 2012, 450,000 apps were available for Android but the estimated number of
downloads since December, 2011 was more than 10 billion.

7. ANDROID ARCHITECTURE:-

8. Version history:-
 Android is updating day by day since its release. These updates to the base operating
system mainly focusing on fixing bugs as well as adding new features to provide more
comfortable environment.
 Generally each new version of the Android operating system is developed under a code
name based on a dessert item.
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9. Version history Cont:-
 The most recent released versions of Android are: -
 2.0/2.1 (Éclair),:-
 which revamped the user interface and introduced HTML5 and Exchange ActiveSync
2.5 support.
 2.2 (Froyo),:-
 which introduced speed improvements with JIT optimization and the Chrome
V8 JavaScript engine, and added Wi-Fi hotspot tethering and Adobe Flash
Player Support.

10. Version history Cont:-
2.3 (Gingerbread):-
 which refined the user interface, improved the soft
keyboard and copy/paste features, and added support for
Near Field Communication
3.0 (Honeycomb):-
 a tablet-oriented release which supports larger screen devices and
introduces many new user interface features, and supports multicore
processors and hardware acceleration for graphics.
 The Honeycomb SDK has been released and the first device
featuring this version, the Motorola Xoom tablet, went on sale in
February 2011.

11. Version history Cont:-
4.0 (Ice Cream):-
 A combination of Gingerbread and Honeycomb into a
"cohesive whole. ”This version had new features added to
the Smartphone’s Such as photo enhancements, offline
email searching, facial recognition unlock, network data,
and usage monitoring.

12. SSL: -The Secure Sockets Layer
 To establish a secure connection, a client must securely
gain access to the public key of the server. In most
client/server setups, the server obtains an X.509 certificate
that contains the server's public key and is signed by a
Certificate Authority (CA).
 When the client connects to the server, the certificate is
transferred to the client. The client must then validate the
certificate.

13. SSL: -The Secure Sockets Layer Cont:-
 The basic validation checks include:
a) Does the subject (CN) of the certificate match the
destination selected by the client?
b) b) Is the signing CA a trusted CA?
c) c) Is the signature correct? And,
d) d) is the certificate valid in terms of its time of
expiry?

14. Android Security: -
 The open nature of Android and its large user base
have made it an attractive and profitable platform to
attack.
 Android kernel to build security measures in; the OS
is sandboxed, preventing malicious processes from
crossing between applications.

15. Android Security Cont:-
 Android is a victim of its own success, not just in the
way it has attracted malicious attention, but in its
very nature. One of the reasons the OS has
succeeded in gaining market share so rapidly is that
it is open source; it is essentially free for
manufacturers to implement.

16. Service:-
 A Service is code that is long-lived and runs without
a UI. A good example of this is a media player
playing songs from a play list.
 In a media player application, there would probably
be one or more activities that allow the user to
choose songs and start playing them.
 However, the music playback itself should not be
handled by an activity because the user will expect
the music to keep playing even after navigating to a
new screen.

17. Features:-
1) Connectivity: -
 Android supports connectivity technologies including
Bluetooth, Wi-Fi.
2) Messaging:-
 SMS and MMS are available forms of messaging,
including threaded text messaging and Android
Cloud to Device Messaging (C2DM)

18. Features Cont:-
3)Java support:-
 While most Android applications are written in Java, there
is no Java Virtual Machine in the platform and Java byte
code is not executed. Java classes are compiled into Dalvik
executables and run on Dalvik, a specialized virtual
machine designed specifically for Android and optimized for
battery-powered mobile devices with limited memory and
CPU.

19. Features Cont:-
4) Bluetooth:-
 sending files (OPP), accessing the phone book
(PBAP), voice dialing and sending contacts between
phones, Keyboard, mouse and joystick.

20. References : -
[1] http://www2.dcsec.uni-
hannover.de/files/android/p50-fahl.pdf .
[2] http://digitalforensicssolutions.
com/papers/android-memory-analysis-DI.pdf .
[3] http://www.4shared.com/.